mirrors/arti.git/crates/tor-proto/src/channel.rs, branch arti-v1.5.0

proto: Add a circuit module shared between client and relay impls.

2025-08-28T10:54:48Z

This is just code motion (I suggest reviewing with `--color-moved`). This also moves the implementation-agnostic parts from `tor_proto::client::circuit` to a new `tor_proto::circuit` module.

proto: Remove the AUTHORIZE as a parsable cell

2025-08-21T15:59:37Z

The AUTHORIZE cell command is simply reserved but not defined. The tor specification, at this point in time, is allowing such cell before the handshake starts but it is very unclear on what ordering is allowed nor how many can are allowed. C-tor silents drop them like VPADDING and so clearly unused. Instead of dealing with it, simply remove its support but keeping its reserved number. Signed-off-by: David Goulet

proto: Rename OutboundClientHandshake

2025-08-20T17:22:16Z

Use the specification terminology which is also the same for ChannelType. Part of #1597 Signed-off-by: David Goulet

proto: Make the OutboundClientHandshake use new cell handler

2025-08-20T17:22:16Z

Use the ChannelFrame<> for the entirety of the outbound client handshake that is the ClientInitiator channel type. With this change, the codec.rs code is not needed anymore along its CodecError as well which has been normalized onto the crate::Error instead in order to simplify error handling and avoid duplication of error types. Unit tests have been modified to reflect this change of what can be done with a channel frame. Also renamed to focus on client behavior. Part of #1597 Signed-off-by: David Goulet

proto: Add helper functions/type for cell handling

2025-08-20T17:22:16Z

This type and functions will be used in the handshake process in future commits. Part of #1597 Signed-off-by: David Goulet

proto: Add channel cell handler

2025-08-20T17:22:16Z

The handler.rs file contains a generic "ChannelCellHandler" which is split into three different handler depending of the channel state (new, handshaking or open). These handlers implement Encoder/Decoder so we can give a ChannelCellHandler to a asynchronous_codec::Framed along a TLS stream. That cell handler is also in charge of tracking the CLOG/SLOG (see tor-spec), running digest of cells seen, which is used to authenticate a channel for the Relay <-> Relay case. This ChannelCellHandler auto transitions as the setters function are used. The handshake code will use this to advance the handler. Each handler uses a MessageFilter from msg.rs in order to allow or not to return the message. A keen eye will notice that we can avoid encoding a message if we don't need but we will decode all possible messages and only then allow it or not. The channel cell handler is not used at this commit. Part of #1597 Signed-off-by: David Goulet

proto: Add restricted channel message sets

2025-08-20T16:41:03Z

Add the msg.rs file containing all the allowed message sets based on the channel type and direction. They are also namespaced by link protocol version. Unused at this commit. They will be used by the channel reactor along the channel type and link protocol version in order to know if the message is allowed or not. See is_allowed() helper function in this commit. Part of #1597 Signed-off-by: David Goulet

proto: Add ChannelType enum

2025-08-20T16:41:03Z

The ChannelType indicates the type of channel in order to dictate which message is allowed on it. The value use the Initiator and Responder terminology from tor-spec documents. At this commit, we only have client channel meaning the "ClientInitiator" type. In future commits, the channel type will be used by the channel reactor to restrict which message is allowed or not. Part of #1597 Signed-off-by: David Goulet

chan: Rename channel launch to launch_client

2025-08-20T16:41:03Z

Signed-off-by: David Goulet

proto: Rename the `tunnel` module to `client`.

2025-08-18T16:09:04Z

The implementation from `tunnel` is client-specific, so we are renaming the module accordingly. The more generic parts will be pulled into a separate module in a future commit.